In the generally practiced art of cheesemaking, milk is clotted or coagulated by means of a clotting enzyme, such as rennin, to form a curd, the curd is cut into multiple pieces and the pieces are collectively cooked. The liquid whey is then separated from the cooked curd which is then subsequently processed to form the desired cheese product. The resulting liquid whey is a principal by-product from the manufacture of cheese and is composed mainly of lactose, proteins, non-proteinaceous nitrogen-containing compounds, inorganic salts and water. The protein constituent of cheese whey would be a valuable item of commerce if it could be separately recovered. Considerable efforts have been made in the past to recover commercial quantities of lactose from cheese whey and such efforts have been moderately successful. These efforts have not allowed the valuable protein to be recovered in any practical amounts. The attempts previously tried to recover the protein from cheese whey have included precipitation techniques and temperature conditions which have either undesirably denatured the protein or have produced precipitates that are difficult to recover. Ultrafiltration and electrodialysis techniques have also been proposed, but these are quite expensive and require undesirably long processing time.